Commit 9ee11f0f authored by Justin Iurman's avatar Justin Iurman Committed by David S. Miller
Browse files

ipv6: ioam: Data plane support for Pre-allocated Trace 

Implement support for processing the IOAM Pre-allocated Trace with IPv6,
see [1] and [2]. Introduce a new IPv6 Hop-by-Hop TLV option, see IANA [3].

A new per-interface sysctl is introduced. The value is a boolean to accept (=1)
or ignore (=0, by default) IPv6 IOAM options on ingress for an interface:
 - net.ipv6.conf.XXX.ioam6_enabled

Two other sysctls are introduced to define IOAM IDs, represented by an integer.
They are respectively per-namespace and per-interface:
 - net.ipv6.ioam6_id
 - net.ipv6.conf.XXX.ioam6_id

The value of the first one represents the IOAM ID of the node itself (u32; max
and default value = U32_MAX>>8, due to hop limit concatenation) while the other
represents the IOAM ID of an interface (u16; max and default value = U16_MAX).

Each "ioam6_id" sysctl has a "_wide" equivalent:
 - net.ipv6.ioam6_id_wide
 - net.ipv6.conf.XXX.ioam6_id_wide

The value of the first one represents the wide IOAM ID of the node itself (u64;
max and default value = U64_MAX>>8, due to hop limit concatenation) while the
other represents the wide IOAM ID of an interface (u32; max and default value
= U32_MAX).

The use of short and wide equivalents is not exclusive, a deployment could
choose to leverage both. For example, net.ipv6.conf.XXX.ioam6_id (short format)
could be an identifier for a physical interface, whereas
net.ipv6.conf.XXX.ioam6_id_wide (wide format) could be an identifier for a
logical sub-interface. Documentation about new sysctls is provided at the end
of this patchset.

Two relativistic hash tables are used: one for IOAM namespaces, the other for
IOAM schemas. A namespace can only have a single active schema and a schema
can only be attached to a single namespace (1:1 relationship).

  [1] https://tools.ietf.org/html/draft-ietf-ippm-ioam-ipv6-options
  [2] https://tools.ietf.org/html/draft-ietf-ippm-ioam-data
  [3] https://www.iana.org/assignments/ipv6-parameters/ipv6-parameters.xhtml#ipv6-parameters-2



Signed-off-by: default avatarJustin Iurman <justin.iurman@uliege.be>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent db67f219

include/linux/ioam6.h

0 → 100644
+13 −0
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: GPL-2.0+ */

/*

 *  IPv6 IOAM

 *

 *  Author:

 *  Justin Iurman <justin.iurman@uliege.be>

 */

#ifndef _LINUX_IOAM6_H

#define _LINUX_IOAM6_H



#include <uapi/linux/ioam6.h>



#endif /* _LINUX_IOAM6_H */

include/linux/ipv6.h

+3 −0
Original line number Diff line number Diff line
@@ -76,6 +76,9 @@ struct ipv6_devconf { 
	__s32		disable_policy;

	__s32           ndisc_tclass;

	__s32		rpl_seg_enabled;

	__u32		ioam6_id;

	__u32		ioam6_id_wide;

	__u8		ioam6_enabled;



	struct ctl_table_header *sysctl_header;

};

include/net/ioam6.h

0 → 100644
+64 −0
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: GPL-2.0+ */

/*

 *  IPv6 IOAM implementation

 *

 *  Author:

 *  Justin Iurman <justin.iurman@uliege.be>

 */



#ifndef _NET_IOAM6_H

#define _NET_IOAM6_H



#include <linux/net.h>

#include <linux/ipv6.h>

#include <linux/ioam6.h>

#include <linux/rhashtable-types.h>



struct ioam6_namespace {

	struct rhash_head head;

	struct rcu_head rcu;



	struct ioam6_schema __rcu *schema;



	__be16 id;

	__be32 data;

	__be64 data_wide;

};



struct ioam6_schema {

	struct rhash_head head;

	struct rcu_head rcu;



	struct ioam6_namespace __rcu *ns;



	u32 id;

	int len;

	__be32 hdr;



	u8 data[0];

};



struct ioam6_pernet_data {

	struct mutex lock;

	struct rhashtable namespaces;

	struct rhashtable schemas;

};



static inline struct ioam6_pernet_data *ioam6_pernet(struct net *net)

{

#if IS_ENABLED(CONFIG_IPV6)

	return net->ipv6.ioam6_data;

#else

	return NULL;

#endif

}



struct ioam6_namespace *ioam6_namespace(struct net *net, __be16 id);

void ioam6_fill_trace_data(struct sk_buff *skb,

			   struct ioam6_namespace *ns,

			   struct ioam6_trace_hdr *trace);



int ioam6_init(void);

void ioam6_exit(void);



#endif /* _NET_IOAM6_H */

include/net/netns/ipv6.h

+3 −0
Original line number Diff line number Diff line
@@ -51,6 +51,8 @@ struct netns_sysctl_ipv6 { 
	int max_dst_opts_len;

	int max_hbh_opts_len;

	int seg6_flowlabel;

	u32 ioam6_id;

	u64 ioam6_id_wide;

	bool skip_notify_on_dev_down;

	u8 fib_notify_on_flag_change;

};
@@ -110,6 +112,7 @@ struct netns_ipv6 { 
		spinlock_t	lock;

		u32		seq;

	} ip6addrlbl_table;

	struct ioam6_pernet_data *ioam6_data;

};



#if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6)

include/uapi/linux/in6.h

+1 −0
Original line number Diff line number Diff line
@@ -145,6 +145,7 @@ struct in6_flowlabel_req { 
#define IPV6_TLV_PADN		1

#define IPV6_TLV_ROUTERALERT	5

#define IPV6_TLV_CALIPSO	7	/* RFC 5570 */

#define IPV6_TLV_IOAM		49	/* TEMPORARY IANA allocation for IOAM */

#define IPV6_TLV_JUMBO		194

#define IPV6_TLV_HAO		201	/* home address option */